The Hollywood star was reportedly involved in a fight with a group of homeless men at the weekend

Police spotted Efron and a man he identified as his bodyguard having a fight with 'at least three other people', according to US website TMZ.

Police on patrol under the Harbor Freeway broke up the fight between Zac - who went to rehab twice last year for cocaine addiction - his bodyguard and the other men, before questioning the Neighbors actor.

When quizzed by cops, the star said he had run out of petrol so they were waiting in the car for a tow.

While waiting, they threw a bottle out of the window and it smashed on the pavement near a group of men who appeared to be homeless. The group, who thought it was being thrown at them, then confronted Zac and his bodyguard.

The actor said two of the homeless group attacked the bodyguard, and when Zac got out of the car he got punched in the mouth.

That Awkward Moment star said: "It was the hardest I've ever been hit in my life."

Cops told TMZ no one was arrested because they viewed it as “mutual combat”.